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copied!<p>Newer versions of GCC (4.4 and later) can inline and optimize a known function pointer using the option <code>-findirect-inlining</code>. This only works when GCC also knows all of the code that uses the pointer.</p> <p>For example, the C library function <code>qsort</code> will <em>not</em> benefit from this optimization. The compiled machine code for qsort is in the library, it expects a function pointer and the compiler cannot change that.</p> <p>However, if you had your own implementation of qsort and you placed it in a header file or you used the very new GCC link-time optimization features, then GCC <em>would</em> be able to take your calling code, the function pointed to, and your qsort source and compile it all together, optimized for your data types and your comparison function.</p> <p>Now, the only times that this really matters is when the function call overhead is much larger than the function itself. In your example of a function that does nothing much, using a function pointer is serious overhead. In my example of a qsort comparison, the function pointer call is also quite expensive. But in some other application like Windows event dispatch, it hardly matters.</p> <p>Since you are using C++ you should study templates. A template function can accept a so-called <code>function object</code> which is just an object that implements <code>operator()</code> <em>and</em> it can accept function pointers. Passing a function object will allow the C++ compiler to inline and optimize almost all of the code involved.</p>

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